Yard Drainage near you

Before any pipe is bought, the ground next to the house has to slope away from it. The Department of Energy's Building America Solution Center states the target as sloping permeable surfaces away from the house at least half an inch per foot for 10 feet, a six-inch drop over the first ten feet, and notes the residential code requirement that impervious surfaces within 10 feet of the foundation slope not less than 2 percent away from the building. Patios, walks and driveways count, which is why a slab that has settled toward the house can produce a wet basement on its own.

Negative grade is more common than homeowners expect, because it develops slowly. Soil settles over a backfilled foundation for years after construction, beds are built up with fresh mulch every spring until the bed is higher than the lawn, and a new patio is poured level with the door rather than pitched away from it. None of this is visible from a distance; a straight board and a level laid against the wall answers it in five minutes.

Where the slope cannot be built, the guidance is to install swales or drains designed to carry water away from the foundation. A swale is simply a shallow shaped channel that moves water across the yard on the surface, and on many lots it is the cheapest, most durable fix available, because there is nothing buried to clog.

Drainage work is a short list of techniques applied to the right problem. Most failures come from applying the wrong one rather than from poor installation.

Surface water is what runs across the ground during and just after rain: roof runoff, driveway runoff, water shed from a neighbor's higher lot. It is handled on the surface, with grade, swales and downspout extensions, and it is by far the cheaper of the two to fix because nothing has to be excavated deeply.

Groundwater is water already in the soil, moving sideways through it or rising with the water table. It is what a French drain or a footing drain intercepts, and it needs a trench, drainage stone, a filter fabric where the soil is fine, correctly bedded perforated pipe with consistent fall, and an outlet somewhere that will accept water by gravity. A French drain installed where the problem is actually surface water often does very little, and a surface fix on a groundwater problem does nothing at all.

The cheap diagnostic is timing. Water that appears during the storm and is gone a few hours later is surface water. Water that arrives a day after the rain and lingers, or that is present in a wet season and absent in a dry one regardless of individual storms, is groundwater. Tell the contractor which pattern you see, because it changes the entire design.

Every drainage design ends at a discharge point, and that is where local rules apply. Portland's city code makes it unlawful to direct water, from any source, on private property to run onto any City sidewalk, street, easement or right of way without first obtaining authorization and approval, and separately requires that drainage from private property, whether from the roof of a building, the surface of a structure, footings of a structure or any other surface, groundwater discharge or other drainage, be conveyed separately from sanitary sewage. Other cities write it differently, but the two ideas recur almost everywhere: roof and ground water do not belong in the sanitary sewer, and you may not simply run your water into the street because it is downhill.

Discharging to the sanitary sewer is the rule people break without knowing. A sump pump or footing drain piped into the house drain overloads the sewer during exactly the storm when it has least capacity, which is how basements back up across a neighborhood. If your sump currently discharges indoors, that is worth resolving before adding any more water to it.

Sending water to the neighbor is the other trap. Even where no ordinance is specific, redirecting concentrated flow onto an adjoining property is the sort of thing that ends in a dispute and occasionally in court. A design that discharges to a swale, an approved storm connection or an infiltration area on your own lot avoids both problems, and EPA's own caution on downspout disconnection is to consider local regulations and where the water will be directed, to avoid property damage, unsafe conditions or other potential problems.

Drainage pricing is driven by excavation and by how far the water has to travel. The variables are the length and depth of trench, what the machine has to cut through, whether equipment can reach the work or it must be dug by hand between a fence and a wall, the number of inlets and cleanouts, whether the design is a surface regrade or a buried system, how far away a legal discharge point is, whether a dry well or infiltration area is needed because there is no gravity outlet, and how much lawn, bed and hardscape has to be restored afterwards. A bid that omits restoration is not a lower price, it is a smaller scope.

LokalMatch is where you start looking. You describe the problem once, including where the water stands, when it appears, what the ground does after rain and where you think it is coming from, and drainage and landscaping contractors serving your area receive the request. Those interested contact you directly. Pros pay for the requests they receive and homeowners use LokalMatch at no cost. LokalMatch does not perform drainage work, does not set prices and does not vet, rank or recommend any contractor, so confirming the discharge point is permitted, that utilities were located, and that the written scope covers restoration is still yours.